nav{
    a{
        width: 150px;
        height: 80px;
        display: block;
        float: left;
        line-height: 80px;
        text-align: center;
        background: grey;
        color: #333;
        transition: all .5s;
        &:hover{
            color: #fff;
            background: #000;
            color: red;
        }
    }
}